Infrared application

It is a commonplace that FTIR-based analyzers are the predominant technology for mid-infrared applications. This arises from a unique tie-in between the inherent advantages of the FTIR method and serious limitations in the mid-infrared range. The most serious problem for mid-infrared spectroscopy is the very low emissivity of mid-infrared sources combined with the low detectivity of mid-infrared thermal detectors. 

E.W. Ciurczak and J.K. Drennen, Pharmaceutical applications of near-infrared-spectroscopy. In Near-Infrared Applications in Biotechnology, R. Raghavachari (ed.), Marcel Dekker Inc., New York, 2001. 

R. Raghavachari (Ed.), Near-Infrared Applications in Biotechnology, Marcel Dekker, New York, 2000. 

For the present work, we chose the constrained method described by Jansson (1968) and Jansson et al (1968, 1970). See also Section V.A of Chapter 4 and supporting material in Chapter III. This method has also been applied to ESCA spectra by McLachlan et al (1974). In our adaptation (Jansson and Davies, 1974) the procedure was identical to that used in the original application to infrared spectra except that the data were presmoothed three times instead of once, and the variable relaxation factor was modified to accommodate the lack of an upper bound. Referring to Eqs. (15) and (16) of Section V.A.2 of Chapter 4, we set k = 2o(k)K0 for 6(k) < j and k = Kq exp[3 — for o(k) > This function is seen to apply the positivity constraint in a manner similar to that previously employed but eliminates the upper bound in favor of an exponential falloff. We also experimented with k = k0 for o(k) > j, and found it to be equally effective. As in the infrared application, only 10 iterations were needed. 

Nonmilitary infrared applications for germanium include C02 lasers (qv), intrusion alarms, and police and border patrol surveillance devices. Germanium is used as a thin-film coating for infrared materials to decrease reflection losses or to provide heavy filtering action below 2 Jim. 

Ferraro JR, Basile LJ (1978) Fourier transform infrared application to national problems In Ferraro JR, Basile U (eds) Fourier transform infrared spectroscopy - applications to chemical systems, Vol 4 Academic Press, New York, 275-302 Ferraro JR, Rein AJ (1985) Application of diffuse reflectance spectroscopy in the far-infrared region In Ferraro JR, Basile LJ (eds) Fourier transform infrared spectroscopy -applications to chemical systems, Vol 4 Academic Press, New York, 244-282 Frank IE, Feikema J, Constantine N, Kowalski BR (1984) Prediction of product quality from spectral data using the partial least squares method J Chem Inf Comput Sci 24 20-24 Fuller MP, Griffiths PR (1980) Infrared microsampling by diffuse reflectance Fourier transform spectrometry Appl Spectrosc 34 533-539... 

Zeller, M.V. Pattacini, S.C. "The Infrared Grating Spectra of Polymers, Infrared Applications Study No. 13", Perkin-Elmer Corp., Norwalk, CT. 1973. 

Arsenic from the decomposition of high purity arsine gas may be used to produce epitaxial layers of III—V compounds, such as InAs, GaAs, AlAs, etc, and as an -type dopant in the production of germanium and silicon semiconductor devices. A group of low melting glasses based on the use of high purity arsenic (24—27) were developed for semiconductor and infrared applications. 

For infrared applications, inhomogeneous a.r. coatings on Ge, extensively investigated by Jacobsson and Martensson [72] have received considerable attention. The films were produced by controlled simultaneous evaporation of Ge and MgF2. A Ge plate coated on both sides with inhomogeneous Ge/MgF2 films with a physical thickness of 1.2 pm increased the transmittance from 48% to more than 90% in the spectral range of 2 to 6 pm [72]. 

For infrared applications, special aluminium mirrors with a protection film which increases the reflection in the near infrared are used. Such mirrors are primarily used in the region above 900 nm. Surface mirrors of gold films which are made to adhere to glass by using special contact layers can be used in the entire infrared spectral region above 600 nm. At approximately 600 nm, the reflectance reaches 90% and from 800 nm it remains constant above 97%. 

The infrared spectrum can be divided into three regions the far infrared (<400cm ), the mid infrared (400CMOOcm 0 and the near infrared (14285-4000 cm i). Most infrared applications employ the mid-infrared region, but the near- and far-infrared regions can also provide information about certain materials. The majority of instruments are set up to scan only the mid-infrared range and this is the re on that we will largely concentrate on in later chapters. 

OPTICAL CONSTANTS OF GLYCINE SULFATE FROM NEAR INFRARED TO FAR INFRARED. APPLICATION TO PYROELECTRICITY. 

Sonmez, G., H. Meng, and F. Wudl. 2003. Very stable low band gap polymer for charge storage purposes and near-infrared applications. Chem Mater 15 4923. 

For most LC displays [14], the cell gap is controlled at aroimd 4 pm so that the required birefringence is smaller than 0.12. Thus Equation (6.13) can be used to describe the wave-length-dependent refractive indices. For infrared applications, high birefringence LC mixtures are required [15]. Under such circumstances, the three-coefficient extended Cauchy model (Equation (6.10)) should be used. 

For infrared applications, a higher birefringence (An > 0.3) compound is needed in order to compensate for the longer wavelength. To obtain a higher birefringence, two approaches can be... 

It is well known that in detection systems the radiation noise level decreases as the temperature of the sensing elements is lowered. In some cases, the improvement in sensitivity is dramatic, particularly in infrared systems. This alone justifies considerable technical effort to develop improved means for maintaining such Ipwered temperatures. It may be profit leto analyze some general factors which prevail in the philosophy of design of cryogenic equipment for infrared application. They are summarized in the following ... 

A photonic device is also found in the literature (Wang et al. 2007) using the thermal insulation properties of porous Si in a photonic crystal reflector for mid-infrared applications. It uses an alternate high-porosity/low-porosity multilayer structure with the high-porosity layers fully oxidized and the low-porosity layers partially oxidized in order to achieve good thermal insulation properties and at the same time enough contrast of the refractive index. 

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